Arabidopsis thaliana response to extracellular DNA: metabolic profile analyses after the exposure to self-DNA_Abstract

The exposure to self-DNA (conspecific DNA) [1], inhibits root growth and seed germination in plants in a concentration dependent manner. Such findings provide a basis for autotoxicity [2] among the mechanisms of plant-soil negative feedback. The inhibitory effect of self-DNA was later extended to other organisms [3-5]. To shed light on the mechanisms underlying the response to self- and nonself-DNA in plants, we evaluated the effect through transcriptomic and metabolomic analyses in the model plant Arabidopsis thaliana [6,7]. Our results highlighted that plants are able to discriminate self- and nonself-DNA. In this work, we describe more in detail the metabolic profiles of the early plants response to self- and nonself-DNA. The results support our transcriptomic analyses [6]. Indeed, a progressive increase in the RNA constituents and nucleotide-based compounds occur only in self-DNA treatments [7] and this could be the consequence of the general reduction of genes expression we previously observed [6]. Conversely, nonself-DNA treatments show no accumulation of specific metabolites in the cells, accordingly with the reported uptake of nonself-DNA [6], this implies that the cell reuses RNA constituents as building blocks. Next step into the analysis of self-DNA inhibition will be the evaluation of the plant long-term response and the effect of epigenetic influence like the changes of methylation patterns and specific chromatin states.